When utilizing automatic yarn filling apparatus on shuttle type looms, it is necessary to eject a spent or used bobbin from the shuttle and strip the small amount of unused yarn from the spent bobbin prior to winding a new filling of yarn thereon. Such an automatic yarn filling apparatus is shown in U.S. Pat. No. 2,766,779. It is essential to the successful operation of the automatic yarn filling apparatus that a free end of the unused yarn be trailing from the spent bobbin a sufficient length to provide a transfer tail. The transfer tail is subsequently caught by a yarn stripper which forms a part of the automatic filling apparatus wherein the bobbin is completely stripped of the unused yarn. If the transfer tail is not adequate to be caught by the yarn stripper, the unused yarn must be unwound by hand or, if not detected, a new filling of yarn will be wound upon the unused yarn which can cause a defect in the material being woven.
Attempts have been made to develop devices for abutting the bobbin following ejection from the shuttle so as to impart a rotation to the bobbin and unwind a sufficient length of unused yarn therefrom. One abutment device is mounted on the shuttle directly below a head of the bobbin as disclosed in U.S. Pat. No. 2,785,702. Another prior art device is illustrated in FIG. 4 as including a flexible insert member mounted on a portion of the loom and extending into the path of the bobbin. However, these type devices are overly protruding and interfere with the natural flight of the bobbin as it descends often retarding the natural rotation of the bobbin. In the latter case, the flexible member must be deflected downwardly for the bobbin to gain passage thereby reducing the energy of the bobbin and, in some instances, the bobbin itself may be deflected outwardly falling to the floor.
Another device for rotating a bobbin is shown in U.S. Pat. No. 3,965,941 issued to the same inventors of the present invention, wherein one jaw of a shuttle spring has a greater vertical width than the opposing jaw so as to spin or rotate the bobbin held therebetween as it is ejected therefrom. While this device has greatly reduced the number of unstripped bobbins delivered from the bobbin stripper, it has been found that the number of unstripped bobbins can be reduced even further when utilizing such a device in combination with the present invention. Furthermore, the device of the present invention need not be limited to use with such a shuttle spring but may also be advantageously and effectively used by itself for reducing the number of unstripped bobbins.